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archish2
April 21st, 2016, 08:51 PM
Fresh install and boot, ram usage is about 1 GB. Anyone else facing this issue? Previous release of ubuntu hovers around 450 MB.


https://bugs.launchpad.net/ubuntu/+source/unity/+bug/1572801

Cheers,

sgian
April 21st, 2016, 10:06 PM
I just noticed it too and confirmed the bug on the launchpad link.

squilookle
April 21st, 2016, 10:12 PM
I have also noticed this. 15.10 used about 700mb on fresh boot, 16.04 is using just over 1GB

yoshii
April 21st, 2016, 10:24 PM
damn, that's discouraging. Are you guys using 32-bit or 64-bit ?

squilookle
April 21st, 2016, 10:59 PM
64 bit. I must say the system is very responsive and CPU usage looks a little low, it's hovering around 0-1% which is good.

The memory usage is higher than I would like to see it but I have plenty so it's not a huge problem for me.

Compiz seems to be taking the most memory so I wonder if it is related to graphics, which is apparently Intel Ivybridge Mobile on this laptop, Incidentally, I've tested some HD video and it looks stunning, much smoother and less screen tearing than I've seen previously so it's actually pretty good so far.

slickymaster
April 21st, 2016, 11:02 PM
Moved to Installation & Upgrades sub-forum

Aeglius
May 18th, 2016, 03:58 PM
I also noticed significant higher memory usage (almost twice, with a single IDE and a browser my 8GB are full!).

I have been observing my RAM usage for some time (suffering from bug #1518457 (https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1518457)), and I have two observations:



When I sum up all RAM usage of individual applications as listed in gnome-system-monitor, the sum is significantly less then the total RAM usage. I can not identitfy any single application or process that has suspiciously higher usage than in 15.10.
The mentioned bug caused my computer to lock up when total used RAM reached around 60% of total available RAM. Now it reaches almost >90%.

I am not expert with the different memory measures (and I know it's not additive since applications share memory).
But my guess is that the measure what gnome-system-memory (or the underlying tools) outputs changed.

richard-stabler
July 5th, 2016, 04:58 PM
I have seen this too. Apparent usage does not explain the 17.1G (55% use). Compiz constantly spinning the processors and has highest RAM usage.

total used free shared buff/cache available
Mem: 31G 1.8G 10G 15G 18G 13G
Swap: 31G 0B 31G

A lot of stuff seems to be stuck in shared buff/cache?!?!?!

Impavidus
July 5th, 2016, 06:49 PM
According to the manual for free:

DESCRIPTION
free displays the total amount of free and used physical and swap mem‐
ory in the system, as well as the buffers and caches used by the ker‐
nel. The information is gathered by parsing /proc/meminfo. The dis‐
played columns are:

total Total installed memory (MemTotal and SwapTotal in /proc/meminfo)

used Used memory (calculated as total - free - buffers - cache)

free Unused memory (MemFree and SwapFree in /proc/meminfo)

shared Memory used (mostly) by tmpfs (Shmem in /proc/meminfo, available
on kernels 2.6.32, displayed as zero if not available)

buffers
Memory used by kernel buffers (Buffers in /proc/meminfo)

cache Memory used by the page cache and slabs (Cached and Slab in
/proc/meminfo)

buff/cache
Sum of buffers and cache

available
Estimation of how much memory is available for starting new
applications, without swapping. Unlike the data provided by the
cache or free fields, this field takes into account page cache
and also that not all reclaimable memory slabs will be reclaimed
due to items being in use (MemAvailable in /proc/meminfo, avail‐
able on kernels 3.14, emulated on kernels 2.6.27+, otherwise the
same as free)
(Use man free too read for yourself.)

There's no stuff stuck in buff/cache, the stuff (most of it, at least) simply remains there until the memory is needed for something else.